We propose to continue our evaluation of complement components in patients with disseminated intravascular coagulation as well as in experimental models. Serum complement components will be quantitated using functional hemolytic assays and immunochemical procedures. Normal and C6 deficient rabbits will be subjected to the slow infusion of thromboplastin and thrombin to elicit disseminated intravascular coagulation. Studies will be performed of complement componenents, platelets and plasma coagulation factors. Emphasis will be placed on the assessment of changes induced on platelet function by administration of the thrombogenic substances and the role of the complement system in mediating such changes.